The alcohol trick works well!

[TmEE]

I clean every game before I put it in my systems as a rule. I don't want someone else's 15 years of corrosion going into my system. For really stubborn games, you can also gently sand the pins with an emery board and then remove the excess grit with rubbing alcohol. Some people go "OMG, NO, HORRIBLE!" but when you don't have any other option, you gotta do what you gotta do.

Never sand the contacts, use pencil eraser instead !!!

Pencil eraser + alcohol = working cart in 99% cases.

[genesisguy]

I have to say that when I cleaned my original games i had from the 90s 6 months ago they were filthy! I woulda never cleaned them had I not come on here though and started collecting other games. My Genesis always worked no matter how dirty the game. This cannot be said for my SNES consoles.

[sonictails]

Oh, and clean your slot with alcohol as well! I use a ruler and a lint free hankerchief. Works mighty fine. I clean my consoles every month and clean the games I regularly play. Actually, it doesn't hurt to clean your games/consoles when you're bored. I know I do.

[The Jackal]

I used to play Sonic Adventure for hours on the DC after having 12+ beers - good times...

[Bablefish]

I use WD 40, I used the alcohol trick before but I find I have to redo it nearly every time I want to play that same game. With WD 40, it's once or twice a year at the most.